![]() ![]() The area of the vents shall be 3½% of the hoistway, but not less than 3 sq. When venting is required, the vents must open directly to the exterior or through noncombustible ducts that terminate at the exterior. Except for Groups R-1, R-2, I-1, I-2, and other occupancies with sleeping units, venting is not required when the building is sprinklered throughout in accordance with NFPA 13 or 13R. ft.Įlevator hoistways penetrating more than three stories are required to provide venting at the top of the hoistways to allow heat and smoke to escape. Existing elevators are exempt from the previous size criteria, provided elevators cars have clear dimensions of 36 inches wide and 54 inches deep, and have a clear floor area of 16 sq. ![]() Additionally, elevator cars with 36-inch-wide side doors may be equally deep, but need only be 68 inches wide. Elevator cars with centered doors may be 51 inches deep (54 inches to the doors) and 80 inches wide, provided the door has a 42-inch minimum width. In ICC/ANSI A117.1, elevator cars shall have a clear dimension of 60 inches wide and 60 inches deep or 54 inches wide and 80 inches deep. ![]() In the IBC, if an elevator is provided in a building that has four or more stories above or below the grade plane, then at least one elevator shall be sized to accommodate an ambulance stretcher that is 24 inches wide by 84 inches long with corners having radii of 5 inches or more. If six elevator cars and two hoistways are provided, then the only combinations permitted would be 3-3 or 2-4 (See C and D in Figure 1)-a 1-5 combination would not be permitted, since no more than four cars are allowed in a single hoistway.įigure 1 - Number of elevator cars in a hoistway.Įlevator car size is also regulated by the IBC and by ICC/ANSI A117.1. Thus, if four elevator cars are provided, then they must be located in two hoistways in a 2-2 or 1-3 combination (See A and B in Figure 1). ![]() However, if four or more elevator cars serve all or the same stories, then the elevators must be located in a minimum of two hoistway enclosures. If multiple elevators are provided in a building, the IBC requires that the number of cars within a single hoistway enclosure be limited to no more than four. The second exception is in Section 403.6, which requires at least two elevators be designated as fire service access elevators in buildings with occupied floors greater than 120 feet above the lowest level of fire department vehicle access. However, the elevator is not required if the building is sprinklered throughout per Section 903.3.1.1 (NFPA 13) or Section 903.3.1.2 (NFPA 13R), and includes either a ramp from the stories, or the stories incorporate a horizontal exit at or above the level of exit discharge. The first exception is in Section 1007.2.1, which requires at least one elevator be provided as one of the required accessible means of egress if an accessible story is located four or more stories above or below the level of exit discharge. The owner or architect may hire an elevator consultant to determine the elevator needs for buildings with high traffic or complex usage requirements.Īs stated, there are a couple of exceptions in which the code regulates the number of elevator cars. With a couple of exceptions, neither the IBC nor ASME A17.1 dictate the number of elevators that must be provided in a building-any number of elevators may be provided at the discretion of the building owner. In addition to the provisions in the IBC, elevators must also comply with the requirements in the American Society of Mechanical Engineers’ (ASME) A17.1, Safety Code for Elevators and Escalators 2, and ICC/ANSI A117.1, Accessible and Usable Buildings and Facilities 3, which are referenced by the IBC. In the International Building Code (IBC) 1, Chapter 30 establishes the primary criteria for elevators, while other sections of the IBC supplement the primary criteria with special provisions, such as requirements for accessible means of egress, elevator lobbies, and shaft enclosures for hoistways. Like other systems within a building, elevators are regulated by the building code. Since its introduction, the elevator has seen numerous advancements, but its purpose remains the same: moving people between floors of multi-story buildings efficiently and safely. Thus, along with the advent of inexpensive materials and advanced engineering and construction methods, the automatic elevator became a pivotal step that led to the surge of high-rise construction in the United States. A little over forty years later, the gearless traction elevator was developed, which allowed movement in buildings of significant height. One hundred and sixty years ago, Elisha Otis invented the first braking mechanism for the elevator, which made vertical travel within a building feasible and safe. ![]()
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